This invention relates to combination apparatus for clamping ground conductor means and for mounting lightning protector means and which combination apparatus is for being mounted on apparatus to be grounded.
Numerous apparatus are known to the art which are grounded, e.g. connected to earth ground to conduct electricity produced by a lightning strike to ground thereby preventing or reducing damage from a lightning strike.
An example of such apparatus is telephone network interface device which device, typically, is mounted on the wall of a subscriber premises and which interconnects incoming telephone lines with subscriber premises lines. To show utility of the present invention, and not by way of limitation, an example of such telephone network interface device is illustrated in FIG. 1 and identified by general numerical designation 10. The telephone network interface device 10 includes a base 12 to which are hingedly mounted a telephone company personnel cover 14 and a subscriber premises cover 16. The telephone network interface device 10 may be, for example, the telephone network interface device illustrated in U.S. Design Pat. No. 297,136 issued Aug. 9, 1988 and assigned to Keptel, Inc., the assignee of the present invention The telephone network interface device 10 of FIG. 1 includes a plurality of lightning protectors 17, 18, 19 and 20 provided at their tops, respectively, with a plurality of telephone terminals 22, 23, 24 and 25 for terminating incoming telephone lines (not shown). Further, the telephone network interface device 10 is provided with a plurality of subscriber terminals 27, 28, 29 and 30 for terminating subscriber premises lines (not shown). The subscriber terminals 27 and 28 and 29 and 30 are interconnected, respectively, to conductors 31 and 32 which terminate, respectively, in plugs 34 and 35 which are received or plugged into jacks 37 and 38. The jacks, in turn, are connected by conductors (not shown) to telephone terminals 22, 23, 24 and 25. The plugs 34 and 35 and jacks 37 and 38 provide demarcation points between the incoming telephone lines and the subscriber premises lines to facilitate determination of whether a fault exists on the incoming telephone lines or the subscriber premises lines, in the manner known to those skilled in the art.
As is known to those skilled in the telephone network interface device art, the lightning protectors 17, 18, 19 and 20 are mounted to the base 12 of the telephone network interface device by prior art apparatus indicated in FIG. 1 by general numerical designation 40 and which apparatus 40 is also for clamping one end of a ground wire 42 the other end of which is connected to earth ground; the prior art clamping apparatus 40 may also clamp a telephone company cable 43 including a plurality of incoming telephone lines 43B (FIG. 2) for interconnection with the telephone company terminals 22, 23, 24 and 25.
The prior art apparatus 40 may be better seen by reference to FIG. 2, and it will be understood, generally, that the combination apparatus for clamping a ground conductor and for mounting a lightning protector of the present invention is an improvement over such prior art apparatus 40.
The prior art apparatus 40, referring now to FIG. 2, includes a physically separate or distinct bracket 45 for being mounted to the bottom 13 (FIG. 1) of the base 12 of the telephone network interface device 10 by threaded fasteners (not shown) inserted through aperture 46 and 47, a physically separate or distinct electrically conductive member 48, and a clamping frame 49. An electrically conductive threaded stud 51 is provided on the top of the bracket 46; as indicated by the dashed lines 55, 56 and 57, the stud 51 is for receiving the outwardly extending electrically conductive connectors 53 and 54 provided on the lightning protectors and the electrically conductive member 48, and which stud 51 in combination with the nut 58 is for mounting and electrically interconnecting the lightning protectors 17, 18, 19 and 20 and electrically conductive member 48. It will be noted particularly that the electrically conductive member 48 is mounted on top of the bracket 45 along with the lightning protectors 17, 18, 19 and 20. The mounting frame 49, FIG. 2, is for being placed over the outer end 61 of the electrically conductive member 48 and upon the ground wire 42 and the ground shield 43A of the telephone cable 43 and the ground wire 42 being placed in the clamping frame 49 the clamping screw 64 is for being threaded inwardly to clamp and electrically interconnect the ground wire 42, the ground shield 43A and the electrically conductive member 48 and thereby in turn electrically interconnect the lightning protectors 17, 18, 19 and 20 to the ground wire 42 and hence to earth ground.
As may be understood by further reference to FIG. 2, the prior art apparatus 40, by being comprised of a plurality of physically separate and distinct members as noted above, is undesirably difficult and time consuming to interconnect to the lightning protectors, ground wire, cable ground shield, and more importantly, as will be further understood, the electrically conductive member 48 upon being mounted to the top of the bracket 45 with the lightning protectors must be undesirably disconnected from the telephone network interface device 10 (FIG. 1) upon the nut 58 being unscrewed or removed to replace the lightning protectors 17, 18, 19 and 20. Such removal of the electrically conductive member 48 renders the telephone network interface device 10 (FIG. 1) ungrounded and thereby subject to lightning damage It has been found that telephone company personnel upon unscrewing the nut 58 to replace or re-wire the lightning protectors 17, 18, 19 and 20 occasionally, inadvertently, forget to reconnect the electrically conductive member 48 thereby leaving the telephone network interface device 10 ungrounded and subject to lightning damage.
Accordingly, there exists a need in the art for new and improved apparatus for both clamping a ground wire and for mounting lightning protectors which is comprised of fewer parts to facilitate mounting to the telephone network interface device and to facilitate interconnection with the lightning protectors, ground wire, etc. Still further, there exists a need for combination ground wire clamping apparatus and lightning protector mounting apparatus which remains mounted to the telephone network interface and electrically interconnected to the ground wire upon the lightning protectors being removed disconnected, such as for removal and replacement, to prevent the telephone network interface device from being inadvertently left ungrounded as described above.